AMPHORA
Introduction
Amphora is a Chess variant inspired in part by the Zuni Indian game of Stone Warriors, and played on a board the shape of a wine jug. The object is take your opponent's King -- either by replacement, diagonal interception, or by telekinesis -- or to stalemate your opponent.Board and Setup
+---+---+---+---+---+
8 | P | P | K | P | P |
+---+---+---+---+---+
7 | P | P | P |
+---+---+---+---+---+
6 | | | | | |
+---+---+---+---+---+---+---+
5 | | | | | | | |
+---+---+---+---+---+---+---+
4 | | | | | | | |
+---+---+---+---+---+---+---+
3 | | | | | |
+---+---+---+---+---+
2 | p | p | p |
+---+---+---+---+---+
1 | p | p | k | p | p |
+---+---+---+---+---+
a b c d e f g
The Pieces
Each player starts the game with a King (K) and seven Pawns (P) on the board as indicated in the diagram above, and a Guard (G) off of the board.The Pawn moves and captures like the Pawn in orthodox chess, with the additional ability to make a non-capturing move to the right or the left. They do not make an initial double move, or promote. The diagonal capturing moves are only allowed for capture by replacement.
+---+---+---+
| + | x | + |
+---+---+---+
| x | P | x |
+---+---+---+
| | | |
+---+---+---+
If a Pawn reaches the back row, it remains there. It may continue to make sideways moves (within the limits on sideways moves -- see below), but can not, of course, capture.
The King moves and captures like a King in orthodox chess, except it may not move or capture orthogonally or diagonally backwards:
+---+---+---+
| * | * | * |
+---+---+---+
| * | K | * |
+---+---+---+
| | | |
+---+---+---+
If the King reaches the back row, the game is over (see below, under capture by telekinesis).
The Guard moves like a King, except it may capture by replacement backwards (but may not move backwards if not capturing):
+---+---+---+
| * | * | * |
+---+---+---+
| * | G | * |
+---+---+---+
| + | + | + |
+---+---+---+
There is one Guard per side, which does not start on the board. Instead, the first time a player's Pawn is captured or the King is placed in check, on that player's next turn, before their move, the Guard may be placed on any vacant square adjacent to the King. This does not count as a move, and the Guard may be moved the turn it is placed. If there is no vacant square adjacent to the King, or the player chooses not to place the Guard, then they may not place the Guard until another Pawn is taken, or the King is placed in check again.
If the Guard reaches the back row, it remains there, unless it can make a backwards capturing move. Otherwise, it may make sideways moves (within the limits on sideways moves -- see below).
Capture
Pieces may be captured by one of three methods: replacement, diagonal interception, or telekinesis. A single move may employ any combination of capture methods.Replacement capture is the normal capture of Chess -- the piece moves to the square of the piece being captured. This is the only type of capture for which a Pawn can move diagonally or a Guard can move backwards.
Diagonal interception occurs when a player moves one of their pieces so that two of their pieces forms a sandwich on the diagonal line around one of their opponent's pieces:
+---+---+---+
| p | | |
+---+---+---+
| | G | |
+---+---+---+
| | | p |
+---+---+-^-+
| | | ^ |
In the above example, white moved their Pawn up to capture the black
guard by diagonal interception. Note that if the white Guard had
moved between black's pieces, it would not have been captured. It is
possible to capture more than one piece (up to four) by diagonal
interception as the result of a single move by simultaneously
forming sandwiches in more than one direction.
Capture by telekinesis occurs upon a piece entering their opponent's back row. When player's Pawn enters their opponent's back row, it may remove one enemy Pawn of the player's choice from anywhere on the board. If their opponent has no Pawns remaining, the player may remove their opponent's Guard. If their opponent has no Guard remaining, the player may remove their opponent's King, winning the game. When player's Guard enters their opponent's back row, the player may remove their opponent's Guard or any of their opponent's Pawns. If their opponent has no Guard remaining, the player may remove their opponent's King, winning the game. When a player's King enters the back row, the player removes their opponent's King, winning the game. A piece starting the turn on player's opponent's back row may not capture by telekinesis, this form of capture only occurs upon entry to the back row.
If a player's Guard enters their opponent's back row, then leaves it via a backwards capture, then enters their opponent's back row again, it may capture by telekinesis each time. Pieces on their opponent's back row may not otherwise capture by telekinesis after their first, entering move.
Movement Restrictions
A player may make no more than three sideways (left or right) moves in a row, among all of their pieces. Thus, if a player moved their King sideways two moves in a row, then a Pawn sideways on their next turn, on the following turn they may not make a sideways move. A backward's capture by the Guard does not count as a sideways move.Other Rules
All other rules are as in orthodox chess, with the exception noted in the introduction that a stalemate is a victory for the other player (that is, the player with no legal move, loses).Note that the concept of check becomes somewhat more complicated because of the capture by diagonal interception. The King is in check any time it has an enemy piece on one of its four diagonals, and another enemy piece is position to move to the opposite diagonal. The white King in the following position is probably in check:
+---+---+---+---+
| P | * | | |
+---+---+---+---+
| | | k | |
+---+---+---+---+
| | | | P |
+---+---+---+---+
The black Pawn to the right doesn't threaten the white King by itself, since it can only capture downward. But if the left-most black Pawn were to move to the right by one square (into the marked square), the white King would be captured by diagonal interception. Hence, the white King is probably in check. Why only probably? Because, if the black player has just completed three sideways moves in a row, they can not make the above capturing move.
Since the Guard can move on the turn it is placed, it could, if the two Kings are only separated by a single, unoccupied space, be placed and capture the opposing King on the same turn. Thus, when the two Kings are separated by only one space, or will be as the result of your move, and your opponent has not yet placed their guard, capturing one of your opponent's pieces or placing your opponent's King in check, is a form of moving into check, and not allowed. For example:
+---+---+---+---+---+
| K | | | | |
+---+---+---+---+---+
| | * | | | |
+---+---+---+---+---+
| | | P | | |
+---+---+---+---+---+
| | | k | | |
+---+---+---+---+---+
White could not capture the black Pawn above, as black could on the following move place their Guard on the marked position and capture the white King.
Notes
The idea of having pieces always move towards the other side of the board, the promotion of one of one's piece when it is captured, and the diagonal interception were all borrowed from the Zuni Indian game of Stone Warriors (Awithlaknakwe), as described by Bell, Culin, Murry and Parlett. (Although, the description in Culin does not really support the restriction of capture in Stone Warriors to diagonal interception; it merely says that a piece is captured when the opponent places it between two of their own pieces.)The amusing and useful term "capture by telekinesis" was coined (as far as I know) by David Parlett, and is found in THE OXFORD HISTORY OF BOARD GAMES.
Play It!
Use Zillions of Games to play this game! If you have Zillions of Games installed, you can download this game and play it.Bibliography
Bell, R.C., BOARD AND TABLE GAMES FROM MANY CIVILIZATIONS, Dover, 1979. Culin, Stewart, GAMES OF THE NORTH AMERICAN INDIANS, Dover, 1975 (original printing 1902). Murry, H.J.R., A HISTORY OF BOARD-GAMES OTHER THAN CHESS, Oxford University Press, 1952. Parlett, David, THE OXFORD HISTORY OF BOARD GAMES, Oxford University Press, 1999.
Written by Peter Aronson.
This is an entry in the contest to design a chess variant on a board with 40 squares.
WWW page created: August 20, 1999. Last modified: November 8, 1999.